(a) Field of the Invention
The present invention relates to a system and a method for controlling impact reduction of an electric vehicle, more particularly, to a system and a method for controlling impact reduction of an electric vehicle that reduces impact generated while releasing a P stage of a shift lever on a sloped road.
(b) Description of the Related Art
Generally, environmentally-friendly vehicles such as an electric vehicle, a fuel cell vehicle and a hybrid electric vehicle are operated by a driving motor which generates torque by electrical energy.
The electric vehicle only uses power of the driving motor operated by power of a battery. On the contrary, the hybrid electric vehicle uses power of an internal combustion engine and power of the driving motor in combination.
If the electric vehicle is parked on a sloped road, torque is exerted on the wheel by a vehicle weight, so that a parking gear, a drive shaft, and a wheel drive shaft are sequentially distorted and energy is accumulated. Thus, the electric vehicle generates a momentary impact in accordance with releasing the accumulated energy. The accumulated energy due to distortion of a driving system may be increased in proportion to the vehicle weight and a degree of a road slope, and may cause a serious impact.
According to a conventional art, hardware systems have been improved such as a structure change of a parking gear or a parking sprag in order to reduce the impact. However, there is a limitation in reducing impact by improving hardware system without reducing the accumulated energy due to distortion of the driving system, which is a root cause of the problem. Moreover, the vehicle provided with a shift by wire (SBW) system uses an actuator of high torque, so the vehicle weight and the manufacturing cost may be increased.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.